Figure 4.

(A, left panel) Lightness constant observer model represented as ground-truth functions that map luminance (x-axis) to the internal lightness dimension Ψ(x) (y-axis) for the three different viewing contexts (color legend). These functions were used to simulate three different experiments: MLDS, MLCM, and asymmetric matching. The middle left and middle right panels show the outcome of estimating perceptual scales by MLDS or MLCM from the simulated responses. The right panel depicts the outcome of a simulated asymmetric matching experiment. (B) and (C) show the same simulation logic for the luminance-based and the contrast-based observer model.